1
2
3
4
5
6
7
8
9
10
11
12
13
14#include <linux/types.h>
15#include <linux/kernel.h>
16#include <linux/string.h>
17#include <linux/errno.h>
18#include <linux/skbuff.h>
19#include <linux/rtnetlink.h>
20#include <linux/module.h>
21#include <linux/init.h>
22#include <net/netlink.h>
23#include <net/pkt_sched.h>
24#include <linux/tc_act/tc_ipt.h>
25#include <net/tc_act/tc_ipt.h>
26
27#include <linux/netfilter_ipv4/ip_tables.h>
28
29
30#define IPT_TAB_MASK 15
31static struct tcf_common *tcf_ipt_ht[IPT_TAB_MASK + 1];
32static u32 ipt_idx_gen;
33static DEFINE_RWLOCK(ipt_lock);
34
35static struct tcf_hashinfo ipt_hash_info = {
36 .htab = tcf_ipt_ht,
37 .hmask = IPT_TAB_MASK,
38 .lock = &ipt_lock,
39};
40
41static int ipt_init_target(struct ipt_entry_target *t, char *table, unsigned int hook)
42{
43 struct xt_tgchk_param par;
44 struct xt_target *target;
45 int ret = 0;
46
47 target = xt_request_find_target(AF_INET, t->u.user.name,
48 t->u.user.revision);
49 if (!target)
50 return -ENOENT;
51
52 t->u.kernel.target = target;
53 par.table = table;
54 par.entryinfo = NULL;
55 par.target = target;
56 par.targinfo = t->data;
57 par.hook_mask = hook;
58 par.family = NFPROTO_IPV4;
59
60 ret = xt_check_target(&par, t->u.target_size - sizeof(*t), 0, false);
61 if (ret < 0) {
62 module_put(t->u.kernel.target->me);
63 return ret;
64 }
65 return 0;
66}
67
68static void ipt_destroy_target(struct ipt_entry_target *t)
69{
70 struct xt_tgdtor_param par = {
71 .target = t->u.kernel.target,
72 .targinfo = t->data,
73 };
74 if (par.target->destroy != NULL)
75 par.target->destroy(&par);
76 module_put(par.target->me);
77}
78
79static int tcf_ipt_release(struct tcf_ipt *ipt, int bind)
80{
81 int ret = 0;
82 if (ipt) {
83 if (bind)
84 ipt->tcf_bindcnt--;
85 ipt->tcf_refcnt--;
86 if (ipt->tcf_bindcnt <= 0 && ipt->tcf_refcnt <= 0) {
87 ipt_destroy_target(ipt->tcfi_t);
88 kfree(ipt->tcfi_tname);
89 kfree(ipt->tcfi_t);
90 tcf_hash_destroy(&ipt->common, &ipt_hash_info);
91 ret = ACT_P_DELETED;
92 }
93 }
94 return ret;
95}
96
97static const struct nla_policy ipt_policy[TCA_IPT_MAX + 1] = {
98 [TCA_IPT_TABLE] = { .type = NLA_STRING, .len = IFNAMSIZ },
99 [TCA_IPT_HOOK] = { .type = NLA_U32 },
100 [TCA_IPT_INDEX] = { .type = NLA_U32 },
101 [TCA_IPT_TARG] = { .len = sizeof(struct ipt_entry_target) },
102};
103
104static int tcf_ipt_init(struct nlattr *nla, struct nlattr *est,
105 struct tc_action *a, int ovr, int bind)
106{
107 struct nlattr *tb[TCA_IPT_MAX + 1];
108 struct tcf_ipt *ipt;
109 struct tcf_common *pc;
110 struct ipt_entry_target *td, *t;
111 char *tname;
112 int ret = 0, err;
113 u32 hook = 0;
114 u32 index = 0;
115
116 if (nla == NULL)
117 return -EINVAL;
118
119 err = nla_parse_nested(tb, TCA_IPT_MAX, nla, ipt_policy);
120 if (err < 0)
121 return err;
122
123 if (tb[TCA_IPT_HOOK] == NULL)
124 return -EINVAL;
125 if (tb[TCA_IPT_TARG] == NULL)
126 return -EINVAL;
127
128 td = (struct ipt_entry_target *)nla_data(tb[TCA_IPT_TARG]);
129 if (nla_len(tb[TCA_IPT_TARG]) < td->u.target_size)
130 return -EINVAL;
131
132 if (tb[TCA_IPT_INDEX] != NULL)
133 index = nla_get_u32(tb[TCA_IPT_INDEX]);
134
135 pc = tcf_hash_check(index, a, bind, &ipt_hash_info);
136 if (!pc) {
137 pc = tcf_hash_create(index, est, a, sizeof(*ipt), bind,
138 &ipt_idx_gen, &ipt_hash_info);
139 if (IS_ERR(pc))
140 return PTR_ERR(pc);
141 ret = ACT_P_CREATED;
142 } else {
143 if (!ovr) {
144 tcf_ipt_release(to_ipt(pc), bind);
145 return -EEXIST;
146 }
147 }
148 ipt = to_ipt(pc);
149
150 hook = nla_get_u32(tb[TCA_IPT_HOOK]);
151
152 err = -ENOMEM;
153 tname = kmalloc(IFNAMSIZ, GFP_KERNEL);
154 if (unlikely(!tname))
155 goto err1;
156 if (tb[TCA_IPT_TABLE] == NULL ||
157 nla_strlcpy(tname, tb[TCA_IPT_TABLE], IFNAMSIZ) >= IFNAMSIZ)
158 strcpy(tname, "mangle");
159
160 t = kmemdup(td, td->u.target_size, GFP_KERNEL);
161 if (unlikely(!t))
162 goto err2;
163
164 if ((err = ipt_init_target(t, tname, hook)) < 0)
165 goto err3;
166
167 spin_lock_bh(&ipt->tcf_lock);
168 if (ret != ACT_P_CREATED) {
169 ipt_destroy_target(ipt->tcfi_t);
170 kfree(ipt->tcfi_tname);
171 kfree(ipt->tcfi_t);
172 }
173 ipt->tcfi_tname = tname;
174 ipt->tcfi_t = t;
175 ipt->tcfi_hook = hook;
176 spin_unlock_bh(&ipt->tcf_lock);
177 if (ret == ACT_P_CREATED)
178 tcf_hash_insert(pc, &ipt_hash_info);
179 return ret;
180
181err3:
182 kfree(t);
183err2:
184 kfree(tname);
185err1:
186 kfree(pc);
187 return err;
188}
189
190static int tcf_ipt_cleanup(struct tc_action *a, int bind)
191{
192 struct tcf_ipt *ipt = a->priv;
193 return tcf_ipt_release(ipt, bind);
194}
195
196static int tcf_ipt(struct sk_buff *skb, struct tc_action *a,
197 struct tcf_result *res)
198{
199 int ret = 0, result = 0;
200 struct tcf_ipt *ipt = a->priv;
201 struct xt_target_param par;
202
203 if (skb_cloned(skb)) {
204 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
205 return TC_ACT_UNSPEC;
206 }
207
208 spin_lock(&ipt->tcf_lock);
209
210 ipt->tcf_tm.lastuse = jiffies;
211 ipt->tcf_bstats.bytes += qdisc_pkt_len(skb);
212 ipt->tcf_bstats.packets++;
213
214
215
216
217 par.in = skb->dev;
218 par.out = NULL;
219 par.hooknum = ipt->tcfi_hook;
220 par.target = ipt->tcfi_t->u.kernel.target;
221 par.targinfo = ipt->tcfi_t->data;
222 ret = par.target->target(skb, &par);
223
224 switch (ret) {
225 case NF_ACCEPT:
226 result = TC_ACT_OK;
227 break;
228 case NF_DROP:
229 result = TC_ACT_SHOT;
230 ipt->tcf_qstats.drops++;
231 break;
232 case IPT_CONTINUE:
233 result = TC_ACT_PIPE;
234 break;
235 default:
236 if (net_ratelimit())
237 printk("Bogus netfilter code %d assume ACCEPT\n", ret);
238 result = TC_POLICE_OK;
239 break;
240 }
241 spin_unlock(&ipt->tcf_lock);
242 return result;
243
244}
245
246static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
247{
248 unsigned char *b = skb_tail_pointer(skb);
249 struct tcf_ipt *ipt = a->priv;
250 struct ipt_entry_target *t;
251 struct tcf_t tm;
252 struct tc_cnt c;
253
254
255
256
257
258
259 t = kmemdup(ipt->tcfi_t, ipt->tcfi_t->u.user.target_size, GFP_ATOMIC);
260 if (unlikely(!t))
261 goto nla_put_failure;
262
263 c.bindcnt = ipt->tcf_bindcnt - bind;
264 c.refcnt = ipt->tcf_refcnt - ref;
265 strcpy(t->u.user.name, ipt->tcfi_t->u.kernel.target->name);
266
267 NLA_PUT(skb, TCA_IPT_TARG, ipt->tcfi_t->u.user.target_size, t);
268 NLA_PUT_U32(skb, TCA_IPT_INDEX, ipt->tcf_index);
269 NLA_PUT_U32(skb, TCA_IPT_HOOK, ipt->tcfi_hook);
270 NLA_PUT(skb, TCA_IPT_CNT, sizeof(struct tc_cnt), &c);
271 NLA_PUT_STRING(skb, TCA_IPT_TABLE, ipt->tcfi_tname);
272 tm.install = jiffies_to_clock_t(jiffies - ipt->tcf_tm.install);
273 tm.lastuse = jiffies_to_clock_t(jiffies - ipt->tcf_tm.lastuse);
274 tm.expires = jiffies_to_clock_t(ipt->tcf_tm.expires);
275 NLA_PUT(skb, TCA_IPT_TM, sizeof (tm), &tm);
276 kfree(t);
277 return skb->len;
278
279nla_put_failure:
280 nlmsg_trim(skb, b);
281 kfree(t);
282 return -1;
283}
284
285static struct tc_action_ops act_ipt_ops = {
286 .kind = "ipt",
287 .hinfo = &ipt_hash_info,
288 .type = TCA_ACT_IPT,
289 .capab = TCA_CAP_NONE,
290 .owner = THIS_MODULE,
291 .act = tcf_ipt,
292 .dump = tcf_ipt_dump,
293 .cleanup = tcf_ipt_cleanup,
294 .lookup = tcf_hash_search,
295 .init = tcf_ipt_init,
296 .walk = tcf_generic_walker
297};
298
299MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
300MODULE_DESCRIPTION("Iptables target actions");
301MODULE_LICENSE("GPL");
302
303static int __init ipt_init_module(void)
304{
305 return tcf_register_action(&act_ipt_ops);
306}
307
308static void __exit ipt_cleanup_module(void)
309{
310 tcf_unregister_action(&act_ipt_ops);
311}
312
313module_init(ipt_init_module);
314module_exit(ipt_cleanup_module);
315
